Persistent Erectile Dysfunction More Likely in 5ARI Users

Longer use of finasteride at a dosage of 1.25 mg/day or less among men younger than 42 years is associated with greater risk, study finds.

Men who take 5-alpha-reductase inhibitors (5ARIs) are at higher risk of persistent erectile dysfunction (PED) after they stop taking the drugs, researchers concluded. The risk was greater in men with longer exposure to the medications.

In a study, new PED lasting 90 days or more developed in 167 (1.4%) of 11,909 men with 5ARI exposure and no prior sexual dysfunction. The median persistence of PED was 1348 days after discontinuing the drugs, a team led by Steven M. Belnap, MD, of the Feinberg School of Medicine at Northwestern University in Chicago, reported online in PeerJ. In addition, of 530 men with new ED, 167 (31.5%) had new PED. Men without prostate disease who combined nonsteroidal anti-inflammatory drug use with more than 208.5 days of 5ARI exposure had a 4.8-fold higher risk of PED than men with shorter exposure.

The study consisted of 691,268 men aged 16 to 89 years, and included 327,437 aged 16 to 42 years (young men). Of 17,475 who were exposed to 5ARIs—finasteride or dutastride—15,634 (89.5%) had no prior diagnosis of ED or low libido or phosphodiesterase use. In this group, new ED developed in 699 (4.5%) and new low libido developed in 210 (1.3%).

PED developed in 34 (0.79%) of 4284 young men exposed to finasteride 1.25 mg/day or less and who had no prior sexual dysfunction and were evaluated for new PED. The median duration of PED was 1534 day after stopping the drug. In addition, 103 of the 4284 men had new ED, and 34 (33%) of these had new PED. Young men with more than 205 days of finasteride exposure had a 4.9-fold higher risk of PED compared with men who had shorter exposure.

Dr Belnap's group concluded that among young men with 5ARI exposure, duration of this exposure was a more accurate predictor of PED than all other assessed risk factors. For every 108 young men exposed for more than 205 days to a finasteride dose of 1.25 mg/day or less—the dose typically used for andogenic alopecia—1 additional young man experienced PED when compared with men who had shorter exposure, the researchers concluded.

“We expect that our finding of an association between debilitating sexual dysfunction and exposure to finasteride or dutasteride will be of particular interest to prescribers and patients considering medical management of androgenic alopecia or symptomatic treatment of prostatic hyperplasia,” they wrote.